Though many things contribute to a younger, healthier appearance, one of the most important is a fibrous protein called collagen. Collagen, especially collagen 1A1 connects and supports skin tissues. It works hand-in-hand with another fibrous protein, elastin. Basically, collagen provides the skin its form and firmness; elastin gives the same skin elasticity and flexibility. In addition, the skin produces other fibrous proteins that provide important linkages to the skin cells. For example, fibrillin protein is expressed in the skin and is intimately associated with elastin, surrounding amorphous elastin filaments and providing additional structure and strength.
As people age, the skin losses collagen because the body gradually produces less and less collagen. In addition, other factors, such as UV light may also contribute to the loss of collagen because these factors may trigger an increased production of proteolytic enzymes that break down collagen. The reduction of collagen and elastin in the skin leads to the appearance of fine lines, wrinkles, age spots, and sagging skin.
Some cosmetic compositions having active agents that supposedly help stimulate collagen production by the body have been disclosed.
U.S. Pat. No. 7,351,745, which is incorporated herein by reference in its entirety, discloses a cosmetic composition containing one or more active agents selected from the group consisting of: L-Theanine, S-Methyl-L-Cysteine, S-phenyl-L-Cysteine. According to the patent, the active agents are found effective to increase expression levels of at least one gene selected from the group consisting of collagen 4, collagen 7 and a few other genes.
U.S. Pat. No. 7,348,034 discloses a cosmetic composition that allegedly works by increasing the synthesis of collagen or elastin and/or preventing or slowing the degradation of collagen and elastin. The composition includes grape seed extract, wolfberry extract, and rosehip. U.S. Pat. No. 7,348,034 is incorporated herein by reference in its entirety.
In spite of these disclosures, there is still a need for active agents that are effective to stimulate the production of collagen and elastin, thus improving the condition and appearance of the skin.
Flavonoids are a class of plant pigments. They are best known for their antioxidant activities. Certain flavonoids have been used in topical compositions.
U.S. Pat. No. 6,093,411 discloses that certain selected flavonoid compounds can be used to prevent or treat skin disorders. The active agent is selected from isoflavones, coumarins, chromones, dicoumarols, chromanones and chromanols.
U.S. Publication 2003/0125264 discloses that flavones, flavonols, flavanones, isoflavanones and isoflavones may be used in the treatment of wounds by increasing proliferation of fibroblast cells.
It has now been surprisingly found that certain prenylated isoflavonoid compounds are effective for inducing a statistically significant upregulation of collagen 1A1 and elastin genes in normal human dermal fibroblasts.
It is therefore an object of the present invention to provide topical compositions containing an appropriate amount of a particular class of isoflavonoid compounds for improving skin condition and appearance.
It is another object of the present invention to provide methods of regulating skin by using the subject compositions.
These and other objects of this invention will become apparent in light of the following disclosure.